Sugru, that multi-purpose moldable plastic, has many fantastic uses. You can do some of the same things, however, for a fraction of the cost by using a kneaded eraser (a.k.a. putty rubber) instead.

It's not exactly the same as Sugru, since the kneaded eraser doesn't harden and continues to be pliable under pressure. However, just like Sugru, you can mold the kneaded eraser around objects or shape it into different forms, as Instructables user robotman9 has found. It's also washable and slightly sticky when worked with.

The biggest benefit is that kneaded erasers cost about a dollar at art or office supply stores.